Re: Invoking a form that was created on a separate thread

Check out the BackgroundWorker or do it yourself (parsing on thread and updating the form with control invoke)

Cheers
Daniel
--
http://www.danielmoth.com/Blog/


"Dannyboy" <daniel@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:%23bFkZNfQFHA.248@xxxxxxxxxxxxxxxxxxxxxxx
Hi Chris your right its not good all, the the thing is the xml files that are being parsed are pretty big and they take quite a bit of time, so I need to put a progress bar on, I did try creating that on the main the and then updating that from a separate thread.

If there is a better way to do this I'm open to all suggestions cos this is p#@*ing me off

Thanks
Dan
"Chris Tacke, eMVP" <ctacke@xxxxxxxxxxxxxxxxxxxxxx> wrote in message news:u9%23zJ0dQFHA.1528@xxxxxxxxxxxxxxxxxxxxxxx
The first question has to be why are you creating a Form on another thread? It's a very bad idea, a bad design, and bad practice.


--
Chris Tacke
Co-founder
OpenNETCF.org
Has OpenNETCF helped you? Consider donating to support us!
http://www.opennetcf.org/donate


"Dan" <daniel@xxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:e5x$vrdQFHA.3628@xxxxxxxxxxxxxxxxxxxxxxx 
Hi everyone

I have a class which parses an xml file and creates a form and its controls from it, and I have recenlty moved this so that it happens on its own thread, I know about controls that are created on a different thread to the UI can not just have its methods called without using invoke so with this I have tried several different ways to get the form to show but I'm having problems.

The ways I have have tried are:

1. With the form that is returned from the parsing class I have tried
me.invoke(new delegateSub(addressof newform.show))
This throws the error "Cannot call Invoke or InvokeAsync on a control until the window handle has been created."

2. Add a controller class that is also created on the separate thread which shows the form when the parsing is complete, this does show the form briefly but it then disappears.

3. With the same controller class I use Application.Run(parsedform). This works beautifully apart from one small snag, the class which starts the parsing is passed a reference to the parser and acts as the code behind for the the controls that are created in the parsed form e.g. the click event of a button in the parsed form is handled by a method in the class that is sent to the parser. This is where this method seems to fall down because the reference no longer works.

Am I fighting a loosing battle with this or can anyone offer some code of wisdom.
Any help will be much appreciated.

Many Thanks
Dan









.